- This paper finds that the benefits to the Scottish mountain hare population from habitat management and predator control on driven grouse moors appear to outweigh the effect of sport shooting or hare control.
- Almost all the UK’s mountain hare population is found in Scotland.
- Mountain hares are thought to be supported by grouse moor management.
- They are also shot for sport, and their populations managed as part of tick control programmes on grouse moors.
- A previous paper suggested steep declines on Scottish grouse moors since 1999.
- This study from 2001-17 counted mountain hare with pointing dogs as part of red grouse counts on driven grouse moors, walked-up moors and moors not managed for grouse.
- Overall, the mountain hare index was higher on driven grouse moors than moors managed for walked-up shooting, or moors with no grouse shooting interest.
Mountain hares are native to the UK and are a protected species. The Scottish Government has a responsibility to monitor their numbers and make sure they are managed in a sustainable way. Historically, they were found across much of Britain, but with the introduction of brown hares and rabbits, the mountain hare is now only found in upland areas. 99% of the UK mountain hare population is in Scotland. Given that mountain hares are well camouflaged and difficult to spot on moorland, their numbers are not easy to monitor. The current population is estimated at 135,000, but the accuracy of that estimate is not known with confidence.
Another factor that makes population estimates difficult is that mountain hare populations often cycle over a period of several years, tending to fluctuate quite widely between the peaks and troughs. A recent study by the Centre of Ecology & Hydrology and RSPB suggests that hare numbers in north-east Scotland have been falling since 1954, with steeper declines since 1999. However, this finding does not agree with data from the GWCT’s National Gamebag Census, which monitors the number of animals shot at its member sites.
Mountain hares and grouse moors
Mountain hares in Scotland are associated with moorland that is managed for red grouse. It is thought that grouse moor management provides good habitat for mountain hares as well as grouse, and that the predator control carried out by gamekeepers also reduces predation of mountain hares. Mountain hares are shot on grouse moors, either for sport, or because they can carry sheep ticks, which can pass a viral illness to grouse. Mountain hares are also managed to protect forestry.
To know whether mountain hare management is sustainable, we need to know whether the benefits of grouse moor management outweigh the impact of shooting and/or control. To do this, we looked at mountain hare numbers on driven grouse moors, walked-up grouse moors and moors not managed for grouse in three regions of the Scottish Highlands.
What they did
Mountain hares were counted every spring between 2001 and 2017 on driven grouse moors, walked-up grouse moors and moors that are not managed for grouse shooting. Walked-up shooting requires lower grouse numbers than driven shooting, so moorland is generally managed at a lower intensity. Counts were carried out when red grouse were counted in spring. 76 different sites across 33 moors were surveyed. Almost 600 individual counts were conducted.
Counting mountain hares accurately is challenging, however using pointing dogs on moorland can give a consistent estimate, which is used as an indicator of hare density in the area. This is called the mountain hare abundance index. This index was analysed relative to the management intensity of the moorland, to see whether the mountain hare index differed between moorland managed for driven shooting, walked-up shooting or no shooting.
What they found
The index of mountain hare numbers was higher on driven grouse moors than either walked-up moors or those not managed for shooting.
There were differences between the three regions covered in the study, both for how much higher the index was, and overall hare population changes, which are summarised below:
- The mountain hare index was more than three times higher on driven moors than on walked-up moors or those not managed for shooting.
- On driven and walked-up moors, over the course of the study there was an overall increase in the mountain hare index of around 5% per year on average.
- All moors considered in this region were managed for grouse.
- The mountain hare index on driven moors was 35 times higher than on moors not managed for shooting, and more than twice as high as on walked-up moors.
- The index was 15 times higher on walked-up moors than those not managed for shooting.
- On driven moors, there was an average 5% per year rise in the mountain hare index, but almost 7% per year decrease on walked-up, and no change for moors with no grouse management.
- The mountain hare index was not significantly different in Tayside between the three management approaches over the course of the study.
- The index was stable on driven moors and it increased on average 10% per year on walked-up moors.
- The mountain hare index dropped by around 40% per year on moors not managed for grouse in Tayside. However, this number should not be compared to the other two categories, because counts were only available for 2001-2011. It could be that this time frame covers the phase of population decline in the cycling process, whereas this may have risen again in the years 2011-2017.
What does this mean?
Overall, more hares were seen on driven grouse moors compared to moors managed for walked-up shooting or not managed for shooting. The differences were more pronounced in Grampian, where the intensity of grouse moor management was higher. The differences in the hare index between management approaches were lowest in Tayside, where the intensity of gamekeeper activity is also lower (as measured by amount of heather burning). Afforestation in Tayside has broken up the moorland environment, which may lead to habitat that is less good for mountain hares.
The results of this study do not agree with the paper published in 2018 by the CEH and RSPB, which found steep declines on grouse moors since 1999, but do support the data from the GWCT’s National Gamebag Census. Differences in the methods used may be at the root of this discrepancy – those used in the study by the CEH and RSPB were not consistent between moors, with some results using pointing dogs, and some relying only on how many hares the observer could see. This is a very difficult approach, which one SNH report found was unlikely to produce a reliable estimate of hare numbers, and may explain the disagreement between studies.
The shared needs of mountain hares and red grouse mean that it is easy to understand how the activities of gamekeepers to benefit one species can also be good for the other. Heather can contribute up to half of the diet of mountain hares, so the managed burning carried out by gamekeepers to ensure a supply of young heather shoots for grouse could improve the food supply for mountain hares as well. Predators are controlled on grouse moors to reduce the impact on red grouse, and as foxes can account for up to 90% of mountain hare mortality, fewer foxes may also help mountain hare survival.
This paper concludes that the balance of benefits to mountain hares from a better food supply and lower predation probably outweighs the impact of sport shooting and tick-management culls, and that it is likely that driven grouse shooting provides an overall conservation benefit to Scotland’s mountain hare population.
Read the original abstract
Hesford, N., Fletcher, K.L., Howarth, D., Smith, A.A., Aebischer, N.J., & Baines, D. (2019). Spatial and temporal variation in mountain hare (Lepus timidus) abundance in relation to red grouse (Lagopus lagopus scotica) management in Scotland. European Journal of Wildlife Research, 65:33: 1-7. doi: 10.1007/s10344-019-1273-7.